Kate Gosselin'Profoundly Concerned'Over Jon Firing Gun

9/25/2013 4:10 PM PDT

Kate Gosselin -- 'PROFOUNDLY Concerned' Over Jon Firing Gun

EXCLUSIVE

Kate Gosselin is gunning for a way to protect her 8 kids from a trigger-happy ex-husband ... TMZ has learned.

Sources familiar with the situation tell TMZ ... Kate is talking to her people about getting the judge in their custody case to modify the order, requiring Jon to exercise restraint when it comes to firing weapons when he has the kids.

We're told she is "profoundly concerned" that Jon was armed last weekend when he left a restaurant, returned home and fired a warning shot in the air to scare a trespassing photog off his property. She says it was an "extreme reaction."

Kate is saying she's dumbfounded that Jon didn't just call 911 to report the trespasser.

We're told she's talking to her people about getting an order requiring Jon to keep all firearms under lock and key when the kids are visiting. She also wants the judge to somehow restrict his right to fire weapons when the children are there.